In folder view activity, when I draw a rectangle using my mouse, while the mouse is in motion, when the left button is up, the drawn selection rectangle doesn't disappear. Even I focus other windows, or click anywhere else on the folder view, it still doesn't disappear.

Reproducible: Always

Steps to Reproduce:
1. Push your left mouse button in folder view
2. Move your mouse
3. While moving your mouse, release the left mouse button
If it doesn't occur, move your mouse faster.

Actual Results:  
A selection rectangle.

Expected Results:  
Selection rectangle should have disappeared when the left mouse button is released.

If I do those steps, I get the expected results:

1. Push your left mouse button in folder view
2. Move your mouse
3. Stop moving your mouse
3. Release the left mouse button

I use Linux, my distribution ArchLinux, KDE version is 5.6.3.
The same problem also occurs for folder widget.